finding carrier in blockade missions

on feburary 6th stay off radar outside plymouth harbor (south england).
docked in harbour will be ARK ROYAL do not destroy it as it wont count ,it MUST be patrolling at point of sinking.
towards 4pm another aircraft carrier will approach from the south ..be ready to positon yourself between the destroyers and the carrier along the path inwards ...ENGINES OFF..,it has 7 destroyers guarding it .
use salvo shooting immediately after sinking ,drop to 40 meters and escape east ....job done...

Start at the outer edge of the Carrier Patrol zone, submerge, speed 1, hard over to either side, time compression. Move toward the center 20 kilometers at a time, repeat. Graphing your progress will be helpful, as destroyer patrols zig zag.

After a couple days of patrolling in this fashion, I detected a carrier convoy with 8 destroyers. I suspect the game mechanics measure both a players activity in a given area, and how much time has passed. The game mechanics produce a viable contact, however, it is up to the player to patrol in a fashion that favors detection. If you are using time compression at higher levels (512, 1024, etc), you will most likely miss the contact, and the game mechanics will likely reset its measurement of your search.

When patrolling an area, I keep time compression down to below 512, higher than 64. I am also zoomed in to include a 20 to 25 kilometer search pattern. Surface to replenish air, move off a few kilometers to a new patrol area, submerge, repeat.